Skip to main content

wolfram cloud - Creating forms with FormFunction with additional elements before input fields


I am trying to construct a simple form that comprises two essential parts. The first part, that comes before input fields is a question containing text (several paragraphs), matrix and so on. The second part is the form with radio buttons to select the right answer.


The second part is simple to do with the following (or similar code, here is only a simple example)


FormFunction[
FormObject[<|
"x" -> <|
"Interpreter" -> {"A" -> 1, "B" -> 2},
"Control" -> RadioButtonBar,
"Label" -> "Select answer"

|>|>], ,
AppearanceRules -> <| |>
]

The problem is that when deployed to Wolfram Cloud the above code generates a page that starts with input fields. The only way to put something before the input fields (here radio buttons) is to use


AppearanceRules -> <|
"Title"-> "Some title",
"Description" -> "Here some description"
|>


The title will be on the very top of the page and description below but before the input fields. There are two problems.



  1. AppearanceRules seems to be completely ignored if FormObject[] is used.

  2. I need Description to contain a couple of paragraphs of text and some simple other elements (like a table).


Questions:



  1. Can anyone confirm the first problem (I am using Mathematica 11.1 but this is cloud related so shouldn't matter)?

  2. What can be passed to Description? In particular, using ExportForm with PNG format I can create an image with text that is properly displayed but this seems like an overkill.

  3. What would be an optimal way to construct such a form? I feel that using FormFunction[] here is like overloading the intended purpose of the function.



Thanks for all help.


Edit.


As suggested by @b3m2a1 (thanks) I tried this.


FormFunction[
{Style["Wow", "Title"],
"This is a different character",
"x" -> <|"Interpreter" -> {"A" -> 1, "B" -> 2},
"Control" -> RadioButtonBar,
"Label" -> "Select choice"|>},

Identity,
PageTheme -> "Blue"
]

This works producing the following form.


Form 1 (works)


However, when I add some other characters like in the following code (note the specific characters).


FormFunction[
{Style["Wow", "Title"],
"This is a different character śćńąśżź",

"x" -> <|"Interpreter" -> {"A" -> 1, "B" -> 2},
"Control" -> RadioButtonBar,
"Label" -> "Select choice"|>},
Identity,
PageTheme -> "Blue"
]

I get the following results (fail).


enter image description here


There is obviously something wrong. The difference between the first working form and the second not working one are only the specific characters.



One thing that is not obvious to me is how can I add a mathematics as an element of description. In more general terms, suppose I want to add the following cell.


Cell[TextData[{
"This is ",
StyleBox["another",
FontWeight -> "Bold"],
" text. This is some mathematical notation ",
Cell[BoxData[
FormBox[
RowBox[{
RowBox[{"F", "(", "x", ")"}], "=",

RowBox[{
SubsuperscriptBox["\[Integral]",
RowBox[{"-", "\[Infinity]"}], "x"],
RowBox[{
RowBox[{"f", "(", "\[Tau]", ")"}],
RowBox[{"\[DifferentialD]", "\[Tau]"}]}]}]}],
TraditionalForm]],
FormatType -> "TraditionalForm"],
". "
}], "Text"]


The capability of adding such elements solves my problem completely.



Answer



Give this a try:


fo =
FormFunction[{
Style["Woopdoop", "Title"],
"ü",
EmbeddedHTML["à"],
"whee" -> <|

"Interpreter" ->
{"asd" -> 1, "asdasd" -> 2},
"Control" -> RadioButtonBar
|>
},
Null
];

ws = Quiet@HTTPHandling`StartWebServer[fo];
"http://localhost:7000" // SystemOpen




HTML


Some unicode characters clearly cause issues. We can get around this by exporting to XML first:


fo =
FormFunction[{Style["Wow", "Title"],
ExportString[
XMLElement["p",
{},
{"This is a different character śćńąśżź"}],

"XML"
],
"x" -> <|"Interpreter" -> {"A" -> 1, "B" -> 2},
"Control" -> RadioButtonBar, "Label" -> "Select choice"|>},
Identity, PageTheme -> "Blue"];
ws = Quiet@HTTPHandling`StartWebServer[fo];
"http://localhost:7000" // SystemOpen

Math


As for math, you can use MathML pretty easily, as it has native support:



fo =
FormFunction[{Style["Wow", "Title"],
ExportString[
XMLElement["p",
{},
{"This is a different character śćńąśżź"}],
"XML"
],
ExportString[
Unevaluated[Integrate[a, {v, 0, Pi}]],

"MathML"
],
"x" -> <|"Interpreter" -> {"A" -> 1, "B" -> 2},
"Control" -> RadioButtonBar, "Label" -> "Select choice"|>},
Identity, PageTheme -> "Blue"];
ws = Quiet@HTTPHandling`StartWebServer[fo];
"http://localhost:7000" // SystemOpen

but I'm not gonna deny that's super ugly. On the other hand, any format a browser can read will work, so you can write something in XML and just export it.


Styled HTML



And we can also use this to add arbitrary styling. But we have to handle the fact that the basic XMLElement[_,{___, "style"->styleString, ___}, ___] method will fail. This implements correct element-specific style exports:


cssStyleBuild[rules_] :=
StringRiffle[
Replace[rules,
(Rule | RuleDelayed)[k_, v_] :>
(ToString[k] <> ":" <> ToString[v]),
1
],
"; "
];

styledXMLExport[xml_, styleRules_] :=
With[{
holdTokens =
AssociationMap[
CreateUUID,
Keys[styleRules]
],
styles =
Association@
Map[

#[[1]] -> cssStyleBuild[#[[2]]] &,
styleRules
]
},
StringReplace[
ExportString[
xml //.
KeyValueMap[
XMLElement[#, r_?(! KeyMemberQ[#, "style"] &), e_] :>
XMLElement[#, Append[r, "style" -> #2], e] &,

holdTokens
],
"XML"
],
KeyValueMap[
"'" <> #2 <> "'" -> "\"" <> styles[#] <> "\"" &,
holdTokens
]
]
]


And then we'll apply that here:


$styles =
{
"p" -> {
"color" -> "blue"
}
};
fo =
FormFunction[{Style["Wow", "Title"],

styledXMLExport[
XMLElement["p", {}, {"asdasd"}],
$styles
],
"x" -> <|"Interpreter" -> {"A" -> 1, "B" -> 2},
"Control" -> RadioButtonBar, "Label" -> "Select choice"|>},
Identity, PageTheme -> "Blue"];
ws = Quiet@HTTPHandling`StartWebServer[fo];
"http://localhost:7000" // SystemOpen


Now you can use styled arbitrary HTML in your text blocks.


Comments

Popular posts from this blog

mathematical optimization - Minimizing using indices, error: Part::pkspec1: The expression cannot be used as a part specification

I want to use Minimize where the variables to minimize are indices pointing into an array. Here a MWE that hopefully shows what my problem is. vars = u@# & /@ Range[3]; cons = Flatten@ { Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; Minimize[{Total@((vec1[[#]] - vec2[[u[#]]])^2 & /@ Range[1, 3]), cons}, vars, Integers] The error I get: Part::pkspec1: The expression u[1] cannot be used as a part specification. >> Answer Ok, it seems that one can get around Mathematica trying to evaluate vec2[[u[1]]] too early by using the function Indexed[vec2,u[1]] . The working MWE would then look like the following: vars = u@# & /@ Range[3]; cons = Flatten@{ Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; NMinimize[ {Total@((vec1[[#]] - Indexed[vec2, u[#]])^2 & /@ R...

functions - Get leading series expansion term?

Given a function f[x] , I would like to have a function leadingSeries that returns just the leading term in the series around x=0 . For example: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x)] x and leadingSeries[(1/x + 2 + (1 - 1/x^3)/4)/(4 + x)] -(1/(16 x^3)) Is there such a function in Mathematica? Or maybe one can implement it efficiently? EDIT I finally went with the following implementation, based on Carl Woll 's answer: lds[ex_,x_]:=( (ex/.x->(x+O[x]^2))/.SeriesData[U_,Z_,L_List,Mi_,Ma_,De_]:>SeriesData[U,Z,{L[[1]]},Mi,Mi+1,De]//Quiet//Normal) The advantage is, that this one also properly works with functions whose leading term is a constant: lds[Exp[x],x] 1 Answer Update 1 Updated to eliminate SeriesData and to not return additional terms Perhaps you could use: leadingSeries[expr_, x_] := Normal[expr /. x->(x+O[x]^2) /. a_List :> Take[a, 1]] Then for your examples: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x), x] leadingSeries[Exp[x], x] leadingSeries[(1/x + 2 + (1 - 1/x...

What is and isn't a valid variable specification for Manipulate?

I have an expression whose terms have arguments (representing subscripts), like this: myExpr = A[0] + V[1,T] I would like to put it inside a Manipulate to see its value as I move around the parameters. (The goal is eventually to plot it wrt one of the variables inside.) However, Mathematica complains when I set V[1,T] as a manipulated variable: Manipulate[Evaluate[myExpr], {A[0], 0, 1}, {V[1, T], 0, 1}] (*Manipulate::vsform: Manipulate argument {V[1,T],0,1} does not have the correct form for a variable specification. >> *) As a workaround, if I get rid of the symbol T inside the argument, it works fine: Manipulate[ Evaluate[myExpr /. T -> 15], {A[0], 0, 1}, {V[1, 15], 0, 1}] Why this behavior? Can anyone point me to the documentation that says what counts as a valid variable? And is there a way to get Manpiulate to accept an expression with a symbolic argument as a variable? Investigations I've done so far: I tried using variableQ from this answer , but it says V[1...